The overall purpose of this proposed research activity is to extend the detailed quantitative analysis of a mass of research data obtained in an extensive program of five interlocking studies of the relationships between drug use and life styles. The studies are part of a research program that has been conducted during the last six years. The series of investigations in this program have examined the life styles of matched groups of men who epitomize the users and abusers of cocaine, amphetamine and its analogues, opiates, barbiturates, and a comparable group of men who have never abused drugs. The men were studied using common procedures, derived from the Representative Case Method, an approach that advocates the intensive study of carefully selected individuals. In each of the five previous studies, detailed intraperson analyses were conducted in which each person was analyzed as his own statistical universe. In addition, interperson data analyses were conducted to determine if there were significant similarities or differences among men who shared a commitment to use of a single drug or class of drugs. However, the intermodular analyses have not yet been undertaken, and the overall findings have not yet been integrated into a single comprehensive report. Funding is requested to complete a large and complex series of inter-group analyses which will compare: all the drug user groups (on the life style measure employed in this program of research) with each other and with non-users of drugs. In addition, separate analyses will be conducted comparing stimulant drug users (users and abusers of cocaine and amphetamine) with depressant drug users (users and abusers of opiates and barbiturates). Finally, all the matched drug user/abuser groups will be collapsed into a single drug user group and will be compared (on the life style measures employed in this research) with the comparable matched group of non-users of drugs. The empirical outcome of this research will be a monograph summarizing the inter-group comparisons and relating them to a comprehensive theory of drug abuse.